Supercharger fuel injection



Marh12,1946. K A BROWNE 2,396,362

SUPERCHARGER FUEL INJECTION Filed Nov. 6, 1943 /l e f Y' ATTORNEY Patented Mar. 12, 1946 UNITED STATE 2.396.362 sursacimncsn FUEL INJECTION Kenneth A. Browne, Ridgewood, N. J., assignor to Wright Aeronautical Corporation, a corporation of New York 4Application November 6, 1943, Serial No. 509,316 7 Claims. (Cl. 26h-90) This invention relates to means for uniformly l. distributing the fuel supply to an internal combustion engine and is particularly directed to internal combustion engines equipped 'withl superchargers.

It is 'an object of this inventionto provide means for uniformly and symmetrically discharg-` front of theing thelfuel intoV the airstream in supercharger impeller.' Unless some means are provided to maintain the pressure in the fuel passage up to the point of discharge of the fuel into the airstream, the low pressure at the entrance to the supercharger evaporation or boiling of the fuel with consequent uneven discharge of the fuel into the airstream.

The symmetry of'discharge from a constant area annular slotor` a plurality of circurnferentially disposed fixed holes from a fuel supply annulus is subject to gravitationalY effects, dynamic pressure effects in the fuel channel leadingto the discharge points; and local variations in the static pressure of the air passing into the supercharger. They magnitude of these factors effecting nony symmetry of fuel distribution areinversely proportional to the pressure drop across the fuel discharge orifice. Due to the operating range covering a to 1 variation in fuel now, the pressure drop across a fixed area fuel discharge Aorifice varies 25 to 1 for the above fuel flow variation.

This results in excessive pressure requirements adequate fuel pressure Y at the highest flow, when drop across the discharge orifice' to provide symmetrical discharge of fuel is provided at the lowest usable fuel flow. Accordingly, it is an object of. this invention to locate a'- fuel pressure control valve directly at the 'point of discharge of the fuel into the airstream.

Other objects of this invention will become apparent uponreading the annexed detailed description in connection with Athe drawing in which: .A i

Fig. lis an axial section cfa supercharger embodying the invention,

Fig. 2 is a section on Fig. 3 is an axial section tion. l.

Referring first to Figs. l and 2, a supercharger impeller I0 is mounted within a portion of the engine casing I2 and is provided with an air intake duct I4, the rear wall of which is illustrated at I6. The air duct I4 delivers air from a, carburetor or other fuel-,air proportioning device shown diagrammatically peller annular intake opening between the impeller hub I3 and shroud I5. 'I'he impeller I0 through a modificaline 2.-2 'of Fig. 1. and

` drive shaft impeller will cause' compresses and delivers the combustible mixture to an intake manifold from 4whence it is distributed to the various engine cylinders. peller I Il is drivably splined to the shaft I8, driven by the internal combustion engine. The impeller the rear wall I6 sleeve 20 is carried by the impeller shaft in cooperation with a bushing member 22 secured to the rear'wall of the intake duct ture so far described is quite conventional, e. g., as more fully illustrated in the copending application, Serial No. 463,559 of F. Wiegand.

A fuel passage 2l extends through the rear wall I6 from vthe fuel-air proportioning means `and terminates in an annular chamber 26 immediately in front of the supercharger impeller and concentric therewith. An annular collar 28 is secured across and closes the impeller end of this chamber and is provided with a plurality of uni- -form and circumferentially disposed valve port vnut 34. The valve member slots or openings 3D. The number of such openings is not important but for symmetry seven or fourteen, e. g., are preferable in a fourteen-cylinder engine. A rotatable collar or valve member 32 is disposed in front of the collar 28 and urged thereagainst by an annular spring member vdisposed between the valve member 32 and `a 32 isprovided with a number of 'circumferentially spaced V-shaped notches 36 corresponding in number and spacing to valve port openings 30 and cooperable there- `with.

As bestseen in Fig. 2, each of the valve ports 30 is elongated. in a direction substantially 45 to a radial direction, and one edge of the associated notch 36 is disposed substantially at right anglesto the longitudinal dimension of the valve port. Obviously this arrangement of the valve 4 is not critical; it is only essential that the notches be adapted to control the size of the valve opening. Thus, one edge of each of the notches 36 is adapted to cover` or uncover more or less of the associated valve port 30 upon rotation of the valve member 32. A radially extending arm 38 is secured to the valve member for operation of the valve. A double 4ended piston member 40, slidably disposed Within a cylinder, is provided with a transverse projection 42 extending through an elongated slot in the cylinder and adapted to be straddled by the forked end 44 of the arm 38. In this way movements of the piston 40 are operable through `the arm 38 to rotatably adjust the valve member 32. One end of the piston is subjected to ports 30 and notches 36 The im-` I8 extends through an opening inl of the air duct and an oil seal' I4. The structhe passage 50, either to the atmosphereor to' `to adjust the valve member the Venturi suction in the airstream of a conventional fuel-air proportioning means. The design is such that the fuel pressure differential between full open and full closed positions ofthe valve member 32 is quite small, whereby a subsure for .opening the valve.

stantially constant fuel pressure is 'maintained-fv on the upstream side of the valve. Furthermore;

with thevent 50 connected to the Venturi suc tion in the airstream, the pressure on the `vent side of the piston decreases with an increase in the magnitude of the fuel flow, thereby helping f to maintain a substantially constant fuel. pressure l'cm-fthe upstream side of -thevalve vmember 32. 'Als`o, thefuelfdischarge valve 32 of thepres.-

entinvention` may comprise-.the fuel discharge, valve -l of thefuel-.air proportioningV mechanism-v disclosed' irlapplicants prior Patent No. 2.165,-I 44'7 In this' prior patent the .end .of a tubular memberiZSQ-'operates' as. .a fueldischarge valve. under'the control of' a .flexible diaphragm 3I` urgedbya springs'in` a'valve closing direction, the oneside of thiszdiaphragm beingsubjected to' fuel discharge pressurel forv openingthe. valve while thel other side 'of? this diaphragm. isconnected'to -achambery 32 subjected .to a substanvalve port means between these members for discharging fuel therethrough against the inclined fiange 60 and thence into the airstream. The cap member 64 is provided with a plurality of circumferentially disposed grooves or recesses 8G comprising valve ports adapted to be uncovered by movement of the valve member 16 to the right. A spring 82 urgesI the valve member in a closing direction and a flexible diaphragm 84 secured to The other side of the diaphragm is vented through passage 86 to theatmosphere .or to the Venturi suction in the 'fairstream Aof the' conventional fuel-air proportioning means. The valve member 16, like valve member 32,.thereupon is automatically operable by the fuel pressure to maintain a substantially constant fuel pressure on its upstream side. Also,

the valve 16 maybe used in connection with the fuel-air proportioning means .disclosed in applic ants aforementioned prior patent as discussed in connectionwith Fig. 1.

In either of the above modifications a valve :t isdisposed at the .'point of discharge of the fuel into the airstream immediately infront of the impellerfor discharging fuel in a symmetrical patternintothe airstream and this v alve is automatically operable to maintain the fuel prest'ially Aconstant pressure .as the atm-sphere.. In

other'words, when used-.With the fuel-air proportionng-deviceof this prior patent, the'herein disclosed fuel-passage 24 is. connected -toifuel passage-29 ofi the prior patent, and. the flexible diaphragm 3| and .associated valve of; the prior patentare replaced' by the herein disclosed movable'piston 40 and its associated valve. 'f Withtheabove. construction the valve mem.- ber 3'2"is`'located directly at the point of discharge o'fthe fuel into theairstream and immediately in" frontof'the superchargerimpeller.'A The valve member'32 automatically operates. to 4maintain thedesir'ed reasonably constant pressureon its upstream sideand theuniformly spacedvalve vports-are operable to effect a symmetrical discharge of -the'fuel intotheimpeller airstream. Thus', upon an increase in the fuel pressure .in the annular chamber 26, the piston 40 operates 32 in an opening direction to .relieve this increase in 'fuel .pressure and'vice versa; Fig', -3 illustrates a modification which generally is similarto Fig. 1 except for the struc-ture -of the'fuel' regulating valve and, inadditionfthe "oil seal sleeve 61 .is provided with' an .outwardly inclined ange. 60 'tor-help .deeCtthe fuel discharged by the valve into fthe airstream in `front -lowing description: A11 annular.. cap. memberlil is secured to the rear vtall-.Gbf the air intake duct 68 to form an annular chamber 1.0 at the end of the fuelpassage I'Zimmediately in front `'other end engages the interior'oflthe,capmember 64. As illustrated in Fig.. 3,- tlrejnterior sur- "face of the cap member 6:4 `is inclined relativeto the valve member 18 such that movement of the valve member to the right in Fig. 3 uncovers sure on its upstream side. 'I'hus..both modificationsillustrate a relatively simple arrangement foreifecting uniform distribution of thefuelinto the airstream.y

While I have described my invention vin detail in its. present preferred embodiment. it vvvill be obvious to those skilledin the art, afterr understanding mv invention] that various changes and modifications may be'made therein without departingfrom the' spirit or scope thereof. I aim in .the appended claims lto cover all such modifications and' changes.

I claimas mv inventiom.

1. In a fuel distributing system for an internal combustionengine eduipned with a suoercharger impellerhavinga hub portioni'a'nri an annular intake openingv about said hub portion, a fuel passage terminatingfadjacent to the Yintake end of said impeller in valve port means, the downstream side of. said valve port means beingy in substantially unrestricted .communication with thefimpeller intake air'stream. said port means being symmetrically disposedv about the impeller .axis .whereby the fuel discharges through said of said valve port means for automatically moving said member in a direction to effect an opening adjustment of said valve port means in response to an increase in said fuel pressure and ..vice versa.

' '2. In a fuel distributing system for an internal `intake `vopening about said hub portion, a fuel oil seal sleeve .member 6| and in clearance rela-i* y f :hambe'r to which fuel is supplied un'der'pressure andhaving valve port means opening substantiallydirectly into the impeller airstream, said chamber being surrounded by the impeller inxtake air'streamv andv disposed adjacent to the intake-"end ofthe irnpellerjhubjsaid valve port means beingso disposed about the impeller axis that the fuel'discharges therethrough symmetrically into the impeller intake airstream at said annular intake opening, a-member movable to effect opening and closing adjustments of said Avalve port means,land means responsive to the fuel pressure upstream of said valve port means for automatically moving said member to effect a valve-port-opening adjustment in response to an increase in fuel pressure and vice versa.

3. In an internal combustion engine, an annular supercharger impeller, an impeller drive shaft, said impeller having an annular air intake opening about'said shaft, an annular fuel chamber disposed about said shaft adjacent to the entrance end of said impeller, said fuel chamber having valve port means symmetrically disposed about said shaft and opening substantially directly into the impeller airstream whereby fuel discharges through said port means symmetrically into said airstream at said annular intake i opening, a member movable to effect opening and closing adjustments of said port means, and means automatically operative to adjust said member in a direction to effect an opening adjustment of said valve port means in response to an increase in fuel pressure on the upstream side of said valve port means side andvice versa.

4. In a fuel distributing system for an internal combustion engine equipped with a supercharger impeller having a hub portion and an annular intake opening about said hub portion, a fuel chamber to which fuel is supplied under pressure disposed adjacent to the intake end of said impeller hub so as to be surrounded by the -impeller airstream, said chamber having a plurality of valve ports opening substantially directly into the impeller airstream, and circumferentially spaced about the impeller axis adjacent the impeller so that -fuel discharges through said ports symmetrically into the surrounding impeller ntake airstream at said annular intake opening, a member rotatable to effect opening and closing `adjustments of said valve ports, said member having an arm projecting radially therefrom, and means operatively engaging said arm and responsive to the fuel pressure upstream of said member for automatically moving said member to effect an opening adjustment of said valve ports in response to an increase in fuel pressure and vice versa.

5. In a fuel distributing system for an internal combustion engine equipped with a supercharger impeller having a hub portion and an annular intake opening about said hub portion, a fuel chamber to which fuel is supplied under pressure disposed adjacent to the intake end of said impeller hub so as to be surrounded by the impeller airstream, said chamber having a plurality of valve ports with their downstream ends in substantially unrestricted communication with the airstream adjacent the impeller, said valve ports being circumferentially spaced about the impeller axis so that fuel discharges therethrough symmetrically into the surrounding impeller intake airstream at said annular intake opening, a member rotatable about the axis of said impeller for controlling said valve ports, and means responsive to the fuel pressure upstream of the member for automatically rotating said member in one direction to effect an opening adjustment of said valve ports in response to an increase in fuel pressure and vice versa.

6. In a fuel distributing system for an internal combustion engine equipped with a supercharger impeller having a hub portion and an annular intake opening about said hub portion, a fuel passage terminating adjacent to the intake end of said impeller in valve port means opening substantially directly into the impeller intake airstream, said port means being symmetrically disposed about the impeller axis whereby the fuel discharges through said port means symmetrically into the impeller intake airstream at said annular impeller intake opening, a member rotatable about the axis of said impeller to effect opening and closing adjustments of said port means, and means responsive to the fuel pressure upstream of said member for automatically rotating said member in a direction to effect an opening adjustment of said valve port means in response toan increase in said fuel pressure and vice versa.

'7. In a fuel distributing system for an internal combustion engine equipped with a supercharger impeller having a hub portion and an annular intake opening about said hub portion, a fuel passage terminating adjacent to the intake end of said impeller in Valve port means opening substantially directly into the impeller intake air stream, said port means being symetrically disposed about the impeller axis whereby the fuel discharges through s aid port means symmetrically into the impeller intake air stream at said annular impeller intake opening, a member coaxial With said impeller axis and axially movable to effect opening and closing adjustments of said port means, and means responsive to the fuel pressure upstream of said member for automatically axially moving said member in a direction to effect an opening adjustment of said valve port means in response to an increase in said fuel pressure and vice versa.

KENNETH A. BROWNE. 

